bad actor vs gremlin

bad actor

noun
  • Used other than figuratively or idiomatically: see bad, actor. 

  • Ill-intentioned, mean, ill-tempered person. 

  • Individual or entity with the prior criminal conviction, or who has been sanctioned by the court or regulator. 

gremlin

noun
  • An imaginary creature reputed to be mischievously inclined to damage or dismantle machinery. 

  • A young, inexperienced surfer, seen as being a nuisance. 

  • Any mysterious, unknown source of mischief or trouble, or the problem created thereby. 

How often have the words bad actor and gremlin occurred in a corpus of books? (source: Google Ngram Viewer )